Using the forum search field I found this conversation. It seems similar to your problem. If you read through that thread and click some links you'll get to documentation on flashing firmware using "Android Device Firmware Update (recommended)". Hope that can help, I don't know the ins and outs myself.
Espruino is a JavaScript interpreter for low-power Microcontrollers. This site is both a support community for Espruino and a place to share what you are working on.
@Claudio
Using the forum search field I found this conversation. It seems similar to your problem. If you read through that thread and click some links you'll get to documentation on flashing firmware using "Android Device Firmware Update (recommended)". Hope that can help, I don't know the ins and outs myself.